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Date: Thu, 31 Jul 2025 17:49:53 +0200
From: Florian Westphal <fw@strlen.de>
To: Dan Moulding <dan@danm.net>
Cc: netfilter-devel@vger.kernel.org, pablo@netfilter.org,
	regressions@lists.linux.dev
Subject: Re: [REGRESSION] v6.16 system hangs (bisected to nf_conntrack fix)
Message-ID: <aIuQoUQQnFMyvJJs@strlen.de>
References: <aIgMKCuhag2snagZ@strlen.de>
 <20250729170228.7286-1-dan@danm.net>
 <aIkHAZjudod05WaR@strlen.de>
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Florian Westphal <fw@strlen.de> wrote:
> Dan Moulding <dan@danm.net> wrote:
> > Ok. I just tried reverting only the changes to nf_conntrack_core.c and
> > the hang no longer occurs. This is on top of 6.16.
> 
> Strange.  Can you completely revert 2d72afb340657f03f7261e9243b44457a9228ac7
> and then apply this patch instead?

Any news?  If you don't have the time to test, could you please share
kernel config or at least some details like CONFIG_PREEMPT settings, if
this uses kasan, kcsan etc.?

I'm asking because I still cannot reproduce any hangs, so I assume that
there is some significant difference between our setups.
While I could ask for a blank revert, that would get back the bug I
was trying to fix and I dislike doing so without understanding the cause
of the new bug first.

Are you using anything more excotic, say, conntrackd, conntrack
helpers, synproxy, or anything like that?

I was able to produce a memory leak by running conntrack_resize.sh
selftest in a loop, but its unrelated bug in ctnetlink.

I will submit a patch later after some more testing.